Figure 4.

Spindle translocation in a cell manipulated to alter the position of the cell center. The cortex of this elongated cell was constricted near one end, such that the cortex became much closer to the upper spindle pole than to the lower spindle pole (B, arrowhead). The spindle gradually moved through the cytoplasm to a central position within the main cell mass (B–E). A cleavage furrow formed between the chromosomes at the center of the cell. The constriction disappeared upon removal of the needle, generating two daughter cells of unequal sizes (H). Time relative to metaphase is shown in the upper right corner. Asterisks indicate the center of the metaphase plate before manipulation. Circles denote the current central position of the spindle. Bar, 20 μm.